TWI826949B - Battery performance evaluation device and battery performance evaluation method - Google Patents

Abstract

The present invention provides a device that can evaluate the performance of a secondary battery while reducing the calculation processing load required to verify the values of model parameters of a model used to evaluate the performance of a secondary battery. Depending on whether the specified conditions are sufficient or insufficient, different battery models are determined as battery models for performance evaluation of the target secondary battery. Specifically, when the specified condition is satisfied, the first battery model defined by the plurality of first model parameters is determined by verifying a portion defined by a smaller number of second model parameters than the plurality of first model parameters. (Battery model determined when specified conditions are not met) The second battery model is a simpler battery model.

Description

Battery performance evaluation device and battery performance evaluation method

The present invention relates to a system for determining the deterioration state of secondary batteries such as lithium ion batteries and the like.

The applicant of this case has proposed a technical method that can determine the degradation state of the secondary battery even if there are no initial measurement results of the characteristic parameters of the secondary battery itself (see Patent Document 1). Specifically, based on the current measurement value V(k) of the voltage V of the secondary battery and the current measurement value I(k) of the current I, according to the multivariable function G representing the initial characteristic model, the past value of the specific voltage V is Initial characteristic estimated value V(0←k). The "initial characteristic model" is a model representing the initial characteristics of a reference secondary battery having the same specifications as the secondary battery to be determined as a target for degradation state.

The applicant of this case proposed a technical method for evaluating the battery performance of a secondary battery using a secondary battery model that expresses the internal resistance of the secondary battery by expressing the impact response of the IIR system and the FIR system respectively (see Patent Document 2 ). [Prior technical literature] [Patent Document]

[Patent Document 1] Japanese Patent No. 6745554 [Patent Document 2] Japanese Patent No. 6842212

[Problem to be solved by the invention]

However, if the number of model parameters that define a model is large, the calculation processing load required to verify the values of the model parameters may become excessive. Therefore, the battery performance evaluation process of a secondary battery mounted on a device may be difficult to mount and execute on the device, and its applicable scope may be limited.

Here, an object of the present invention is to provide a device that can evaluate the performance of a secondary battery while reducing the calculation processing load required for verifying the values of model parameters that define a model for evaluating the performance of the secondary battery. [Means for solving problems]

The battery performance evaluation device according to the present invention includes a first recognition processing element for recognizing the measurement result of the impedance of the reference secondary battery, based on the measurement result of the impedance of the reference secondary battery recognized by the first recognition processing element. , when the specified conditions are not met, the first battery model defined by the plurality of first model parameters is determined by verifying the respective values of the plurality of first model parameters, and when the aforementioned specified conditions are met, the first battery model is determined by verifying the respective values of the plurality of first model parameters. 1. The first calculation processing element of the second battery model defined by the plurality of second model parameters is determined by the respective values of a smaller number of second model parameters, for a secondary battery having the same specifications as the aforementioned reference secondary battery. The second recognition processing element for recognizing the actual measured output voltage, which is a measurement result of the change pattern of the voltage output by the target secondary battery when a specified current is input to the target secondary battery, is determined by the aforementioned first calculation processing element The first battery model or the second battery model is a second calculation process for specifying the model output voltage as a change pattern of the voltage output by the first battery model or the second battery model when the specified current is input. elements, and battery performance evaluation elements for evaluating the performance of the subject secondary battery based on a comparison result between the actual measured output voltage recognized by the second recognition processing element and the model output voltage specified by the second calculation processing element. .

According to the battery performance evaluation device related to the present invention, different battery models are determined as battery models for performance evaluation of the target secondary battery depending on whether the specified conditions are sufficient or insufficient. Specifically, when the specified condition is satisfied, the first battery defined by the plurality of first model parameters is determined by verifying the portion defined by the second plurality of model parameters that is smaller than the plurality of first plurality of model parameters. Model (a battery model determined when the specified conditions are not met) is a second battery model that is a simpler battery model. Therefore, compared with a case where the first battery model is established regardless of the sufficiency of the specified conditions, it is possible to reduce the calculation processing load required for the verification process of the model parameters of the battery model used for performance evaluation of the target secondary battery.

(Construction of battery performance evaluation device)

A battery performance evaluation device 100 as an embodiment of the present invention shown in FIG. 1 is composed of a database 10 and a target machine 200 and one or a plurality of servers that can communicate through a network. The battery performance evaluation device 100 evaluates the performance of the secondary battery 220 installed as a power source in the target device 200 .

The battery performance evaluation device 100 includes a first recognition processing element 111, a second recognition processing element 112, a first calculation processing element 121, a second calculation processing element 122, a battery performance evaluation element 130, and an information provision element 132. The first recognition processing element 111, the second recognition processing element 112, the first calculation processing element 121, the second calculation processing element 122, the battery performance evaluation element 130 and the information providing element 132 are respectively composed of a processor (calculation processing device) and a memory. (memory device) and I/O circuits. In addition to various data indicating the measurement results of the voltage response characteristics of the secondary battery 220 for a specified current, a program (software) is stored in the memory or a different memory device. For example, a plurality of identification codes for identifying the type (specified by specifications or performance elements) of the secondary battery 220 or the target device 200 in which it is mounted, and a plurality of secondary battery models are associated with each other. Relationships and memories remain in memory.

The processor reads the necessary program and data from the memory, and based on the data, executes the calculation processing according to the program to execute the calculation processing described below assigned to each element 111, 112, 121, 122, 130 and 132 or task. The so-called "recognition" of information by each element means receiving information, retrieving or reading information from information sources such as the database 10, and performing calculations, inferences, specifics, verifications, predictions, etc. on the information by performing calculations on the basic information. Prepare various calculation processing of information or data necessary for subsequent calculation processing.

The target device 200 includes an input interface 202, an output interface 204, a control device 210, a secondary battery 220, and a sensor group 230. The target device 200 includes various devices that use the secondary battery 220 as a power source, such as personal computers, mobile phones (smartphones), home appliances, and mobile objects such as electric bicycles.

The control device 210 is composed of a processor (arithmetic processing device), a memory (storage device), an I/O circuit, and the like. Various data such as measurement results of the voltage response characteristics of the secondary battery 220 are stored in this memory or in a different memory device. The control device 210 operates in response to the power supplied from the secondary battery 220, and controls the operation of the target device 200 in the energized state. The operation of the target machine 200 includes the operation of the actuator (electric actuator, etc.) constituting the target machine 200 . The processor constituting the control device 210 reads necessary programs and data from the memory, and executes calculation processing assigned according to the program based on the data.

The secondary battery 220 is, for example, a lithium-ion battery, or other secondary batteries such as a nickel-cadmium battery. The sensor group 230 measures the values of parameters necessary for controlling the target device 200 in addition to the voltage response characteristics and temperature of the secondary battery 220 . The sensor group 230 is composed of, for example, a voltage sensor, a current sensor, and a temperature sensor that output signals respectively corresponding to the voltage, current, and temperature of the secondary battery 220 .

The battery performance evaluation device 100 may be mounted on the target device 200 . In this case, the software server (not shown) can also transmit a message (battery software) to the arithmetic processing device constituting the control device 210 of the target machine 200, and provide the battery performance evaluation to the arithmetic processing device. Function of device 100.

(Battery performance evaluation method) The battery performance evaluation method of the secondary battery 220 (target secondary battery) executed by the battery performance evaluation device 100 configured as described above will be described below.

(Understanding the measurement results of impedance) The first process recognition processing element 111 of the battery performance evaluation apparatus 100 recognizes the measurement results of impedances such as the complex impedance Z of the secondary battery 220 as various types of reference secondary batteries (FIG. 2/STEP 112). The complex impedance Z of the reference secondary battery is measured by the AC impedance method, and the measurement result is associated with an identification code for identifying the type of the reference secondary battery and recorded in the database 10 .

The complex impedance Z of the secondary battery 220 that is a reference secondary battery that is not mounted on the target device 200 is measured. In addition, the complex impedance Z of the secondary battery 220 serving as a reference secondary battery in a state mounted on the target device 200 may also be measured. For example, the target device 200 is connected to a power source such as a commercial power source in order to charge the secondary battery 220, and outputs a sine wave signal based on the power supplied from the power source.

In FIG. 4A , an example of a Nyquist plot showing actual measurement results of the complex impedance Z of the secondary battery 220 is shown together with an approximate curve of the plot. The horizontal axis is the real part ReZ of the complex impedance Z, and the vertical axis is the imaginary part -ImZ of the complex impedance Z. In the area of -ImZ>0, the larger ReZ is, the complex impedance Z at low frequency. The value of ReZ where -ImZ=0 is equivalent to the moving resistance in the electrolyte of the secondary battery 220 . -The radius of curvature of the approximately semicircular portion of the region where ImZ>0 corresponds to the charge transfer resistance of the secondary battery 220 . This curvature radius tends to become smaller as the temperature T of the secondary battery 220 becomes higher. -The linear portion standing at about 45° in the low-frequency region in the region where ImZ>0 reflects the influence of the Warburg impedance of the secondary battery 220.

(Establishment of secondary battery model) In the battery performance evaluation device 100, the first calculation processing element 121 determines whether the specified condition is satisfied (FIG. 2/STEP 114). The specified condition is, for example, the condition that the specified current applied to the secondary battery 220 as the target secondary battery is composed of a low-frequency current component lower than the sampling frequency. For example, in the Nyquist diagram shown in FIG. 4A , the frequency (~1 Hz) at a linear rise of about 45° in the low-frequency region corresponding to the region of -ImZ>0 may be used as the sampling frequency. For example, a current composed of a low-frequency current component corresponding to the charging and discharging current of the secondary battery 220 should be the specified current.

In addition to or instead of this condition, the condition that the arithmetic processing load (CPU usage, etc.) of the first arithmetic processing element 121 is above the reference value and the performance of the secondary battery 220 of the target device 200 can be evaluated as required accuracy or emergency. The conditions of devices whose performance is below the threshold (for example, devices such as mobile phones and personal computers that have a very low degree of performance degradation caused by the performance degradation of the secondary battery 220), and/or the conditions of the secondary battery 220 that is the subject of this performance evaluation. The condition that the elapsed period from the previous performance evaluation time point has not yet reached the specified period is defined as the specified condition.

When it is determined that the specified condition is not satisfied (FIG. 2/STEP 114‥NO), based on the measurement result of the complex impedance Z of the secondary battery 220 as the reference secondary battery recognized by the first recognition processing element 111, the first The respective values of the plural first model parameters of the 1 battery model are verified at different temperatures (Figure 2/STEP116).

The first battery model is a model representing the voltage V(z) output from the secondary battery 220 when the current I(z) is input to the secondary battery 220 . The first battery model (complete model), for example, shown in Figure 3A, is composed of a resistance r ₀ equivalent to the moving resistance in the electrolyte, a Warburg impedance W, a resistance _ri equivalent to the charge moving resistance, and a capacitance C _i The ith RC parallel circuit (i=1,2,‥,m) formed, and the LR parallel circuit formed by the coil L and the resistor r _L are defined by the equivalent circuit connected in series.

The number of RC parallel circuits connected in series may be smaller than 3 or larger than 3. The Warburg impedance W can be connected in series with the resistor R at least in a certain RC parallel circuit. Capacitor C can also be replaced by CPE (Constant Phase Element).

In the first battery model, the transfer function H ₁ (z) using the open voltage OCV(z) of the secondary battery 220 and the internal resistance is defined by the relational expression (11).

Here, OCV(z) indicates that the open voltage increases or decreases as the current I(z) is charged and/or discharged.

The transfer function H ₁ (z) of the resistance within the first battery model is the transfer function H ₀ (z) of the resistance r ₀ defined by the relational expression (12), and the i-th RC defined by the relational expression (13). The transfer function H _i (z) of the parallel circuit, the transfer function H _W (z) of the Warburg impedance W defined by the relational expression (14), and the transfer function H _L of the LR parallel circuit defined by the relational expression (15) (z), defined by relation (16).

Here, a _i , b _i0 and b _i1 use the sampling period T and are expressed by coefficient relational expressions (131) and (132).

The transfer function h _W (s) of the Warburg impedance W fitted to the experimental data is expressed by the relational expression (141) or (142) in the frequency region.

This transfer function is expanded to FIR and expressed by relational expressions (14) to (16) to correspond to the impact response.

The approximate curve of the complex impedance Z of the secondary battery represented by the Nyquist diagram marked with a solid line in FIG. 4A is conveyed by the equivalent circuit model that defines the internal resistance of the secondary battery according to the relational expression (16). It is calculated under the assumption of function H(z). Thereby, the values of the first model parameters r ₀ , r _i , C _i , w ₁ , w ₂ , w ₃ , r _L and L are obtained (refer to relational expressions (12) to (15)). Table 1 shows an example of the verification results and time constant of the first model parameter value.

The value of the open voltage OCV of the secondary battery model is verified by the measured value of the open voltage OCV (refer to the relationship equation (11)). Next, based on the value of the parameter, the first battery model establishes the secondary battery 220 serving as a reference secondary battery with various performances or specifications.

On the other hand, when it is determined that the specified condition is satisfied (FIG. 2/STEP 114‥YES), the measurement result of the complex impedance Z of the secondary battery 220 as the reference secondary battery recognized by the first recognition processing element 111 is used. , the respective values of the plural second model parameters defining the second battery model are verified at different temperatures (Figure 2/STEP118).

The second battery model is a model that represents the voltage V(z) output from the secondary battery 220 when the current I(z) is input to the secondary battery 220 , similarly to the first battery model. The second battery model is a time constant of the transfer function H _i (z) of the i-th RC parallel circuit defined by the relational expression (13). When the time constant is sufficiently smaller than the sampling period T, it can be compared with the first battery model. Simplified model. For example, the second battery model, as shown in FIG. 3B , is defined by an equivalent circuit in which a single resistor R ₀ and a Warburg impedance W are connected in series.

The second battery model is defined by the relational expression (21) using the transfer function H ₂ (z) of the open voltage OCV(z) of the secondary battery 220 and the internal resistance.

The transfer function H ₁ (z) of the resistance within the second battery model is the transfer function H ₀ (z) of the resistance R ₀ defined by the relational expression (22) and the Warburg impedance W defined by the relational expression (14). The transfer function H _W (z) is defined by relation (26). The resistance R ₀ is the result of integrating the resistance r ₀ corresponding to the moving resistance and the resistance r _i (i=1, 2,‥,m) corresponding to the charge moving resistance in the electrolyte solution, and is regarded as a single resistance.

The approximate curve of the complex impedance Z of the secondary battery represented by the Nyquist diagram marked with a solid line in FIG. 4B (especially the linear part in the region of -ImZ>0), according to the relational expression (26 ) is obtained under the assumption of the transfer function H(z) of the equivalent circuit model that defines the internal resistance of the secondary battery. Thereby, the values of the second model parameters r ₀ , r _i , w ₁ , w ₂ and w ₃ are obtained (refer to relational expressions (22) and (14)). The value of the open voltage OCV of the secondary battery model is verified by the measured value of the open voltage OCV (refer to the relationship equation (21)). Next, based on the value of the parameter, the second battery model establishes the secondary battery 220 as a reference secondary battery with various performances or specifications.

The number of the second model parameters (R ₀ , w ₁ , w ₂ , w ₃ ) is “4”, which is larger than the number of the first model parameters (r ₀ , r _i (i=1～3), C _i (i=1～ 3) The number of w ₁ , w ₂ , w ₃ , r _L , L) is still less than "12". In addition, a part of the second model parameters are parameters (w ₁ , w ₂ , w ₃ ) that define the Warburg impedance W, and are the parameters (w ₁ , w ₂ ) that define the Warburg impedance W in the same way as a part of the first model parameters. , w ₃ ) are common.

(Second battery performance evaluation) In the target device 200, it is determined whether the first condition is satisfied by the power-on state control device 210 (FIG. 2/STEP 212). As the "first condition", for the target device 200 , conditions such as a request for battery performance evaluation of the secondary battery 220 through the input interface 202 and the fact that the target device 200 is connected to an external power source for charging the secondary battery 220 are adopted. The battery performance evaluation device 100 recognizes the identification code ID for identifying the performance and/or specifications of the secondary battery 220 as the target secondary battery based on communication with the target device 200 at an appropriate timing.

If it is determined that the first condition is not satisfied (Fig. 2/STEP 212‥NO), the adequacy judgment process of the first condition is executed again (Fig. 2/STEP 212). The adequacy determination process of the first condition (Figure 2/STEP212) can also be omitted.

When it is determined that the first condition is satisfied (FIG. 2/STEP 212 ‥YES), the specified current I(t) that changes with time in the aspect shown in FIG. 5A is input to the secondary battery 220 as the target secondary battery ( Figure 2/STEP214). The waveform signal specifying the current I(t) may also be specified by the second recognition processing element 112 through mutual communication between the battery performance evaluation device 100 and the target device 200 . For example, a pulse current generator mounted on the target device 200 is driven by power supplied from an external power source connected to the target device 200 , and the specified current I(t) generated by the pulse current generator supplies the secondary battery 220 with power. Enter. An auxiliary power supply for generating a specified current may also be mounted on the target device 200 .

According to the output signal of the sensor group 230, the voltage response characteristic V(t) and the temperature T of the secondary battery 220 are measured by the control device 210 (FIG. 2/STEP 216). Thereby, for example, the voltage response characteristic V(t) of the secondary battery 220 that changes as shown by the solid line in FIG. 5B is measured.

Next, the control device 210 determines whether the second condition is satisfied (FIG. 2/STEP 218). As the "second condition", a sufficient waveform signal is obtained to specify the voltage response characteristic V(t), a specific time elapses from the first time point when it is finally determined that the first condition is satisfied, and the second time point is reached, There are conditions such as a request for battery performance evaluation of the secondary battery 220 in the target device 200 through the input interface 202 .

If it is determined that the second condition is not satisfied (Fig. 2/STEP 218‥NO), the adequacy judgment process of the first condition is executed again (Fig. 2/STEP 212). The adequacy judgment processing of the second condition (Figure 2/STEP218) can also be omitted.

When it is determined that the second condition is satisfied (FIG. 2/STEP 218‥YES), the measurement results of the voltage response characteristic V(t) and temperature T of the secondary battery 220 are transmitted to the target device through the transmitting device constituting the output interface 204. 200 sends a message to the battery performance evaluation device 100 (Fig. 2/STEP 220). Furthermore, when the voltage response characteristic V(t) is measured, measurement condition information for specifying the specified current I(t) input to the secondary battery 220 may be transmitted from the target device 200 to the battery performance evaluation device 100 .

In the battery performance evaluation device 100, the second recognition processing element 112 recognizes the measurement results of the voltage response characteristic V(t) and the temperature T of the secondary battery 220 as the second measurement result (FIG. 2/STEP 122).

The second calculation processing element 122 selects the identification code ID associated with the second measurement result and the temperature included in the second measurement result from among a plurality of secondary battery models registered in the database 10 The first battery model or the second battery model for each of the measurement results of T (Figure 2/STEP124). When there is no first battery model for evaluating the performance of the secondary battery 220 of the target secondary battery, or when there is a second battery model, the second battery model may be selected. When there are both a first battery model and a second battery model, any one of the battery models (for example, the first battery model with more or less superior performance evaluation accuracy) may be selected with priority.

Furthermore, the second calculation processing element 122 inputs the designated current I(t) to the selected first battery model or second battery model (FIG. 2/STEP 126). The specified current I(t) may be recognized based on the waveform signal specified by the second recognition processing element 112, or may be recognized based on the measurement condition information transmitted from the target device 200 to the battery performance evaluation device 100.

By the second calculation processing element 122, the voltage response characteristic V _model (t) output by the first battery model or the second battery model is specified as the output signal of the first battery model or the second battery model (Fig. 2/ STEP128). Thereby, for example, the voltage response characteristic V _model (t) of the second battery model that changes as shown by the dotted line in FIG. 5B is specified as the output signal of the secondary battery model.

Next, the battery performance evaluation element 130 compares the voltage response characteristic V(t) of the secondary battery 220 as the target secondary battery with the voltage response characteristic _Vmodel (t) of the first battery model or the second battery model. As a result, the performance of the secondary battery 220 is evaluated (Fig. 2/STEP 130). For example, the similarity x of the curves respectively representing the voltage response characteristic V(t) of the secondary battery 220 as the target secondary battery and the voltage response characteristic _Vmodel (t) of the secondary battery model is specified. Next, the deterioration degree D(i)=f(x) of the secondary battery 220 is specified according to the decreasing function f with the degree of similarity x as the main variable ("i" is an index indicating the type of the secondary battery 220). That is, the higher the degree of similarity x is, the lower the degree of deterioration D is evaluated. On the contrary, the lower the degree of similarity x is, the higher the degree of deterioration D is evaluated.

The battery performance evaluation element 130 generates deterioration diagnosis information Info(D(i)) corresponding to the degree of deterioration D(i) of the secondary battery 220 (FIG. 2/STEP 132). Through the battery performance evaluation element 130, the diagnostic information Info(D(i)) is sent from the battery performance evaluation device 100 to the target device 200 (FIG. 2/STEP 134).

In the target device 200, the reception device constituting the input interface 202 receives the degradation diagnosis information Info(D(i)) (FIG. 2/STEP 222). The display deterioration diagnosis information Info(D(i)) is output to the display device constituting the output interface 204 (FIG. 2/STEP 224). Therefore, in addition to the graph display showing the degree of deterioration D(i) of the secondary battery 220, "The degree of deterioration of the battery is 30%. It is recommended to replace it after 150 days." is related to the processing method corresponding to the degree of deterioration D(i), etc. The message is displayed on the display device.

(Other embodiments of the present invention) In the aforementioned embodiment, the first battery model and/or the second battery model are selected with reference to the temperature T at the time of measurement of the voltage response characteristics V(t) of the secondary battery and the target secondary battery, and the second battery model is evaluated. Performance of secondary battery 220. On the other hand, in other embodiments, the temperature T at the time of measurement of the voltage response characteristics V(t) of the reference secondary battery and the target secondary battery may not be considered, but may be based on the identification indicating the performance of the target secondary battery, etc. The code selects the first battery model and/or the second battery model, and evaluates the performance of the secondary battery 220 as the target secondary battery.

[Effects of the invention] According to the battery performance evaluation apparatus 100 related to the present invention and the battery performance evaluation method executed thereby, different battery models are determined as battery models for performance evaluation of the target secondary battery depending on whether the specified conditions are sufficient or insufficient. Specifically, when the specified condition is satisfied, a second battery model smaller than the first battery model is determined from the first battery model defined by a plurality of first model parameters (the battery model is determined when the specified condition is not satisfied). The second battery model is a simplified battery model defined by parameters (refer to Figure 2/STEP114‥YES→STEP118). Therefore, compared with the case where the first battery model is established regardless of the sufficiency of the specified conditions, it is possible to achieve the verification process required for the model parameters of the battery model used for performance evaluation of the secondary battery 220 as the target secondary battery. Reduction of calculation processing load.

10:Database 100:Battery performance evaluation device 111: The first cognitive processing element 112: The second cognitive processing element 121: The first calculation processing element 122: Second calculation processing element 130:Battery performance evaluation device 200:Target machine 202:Input interface 204:Output interface 210:Control device 220: Secondary battery 221: Refer to secondary battery 222: Target secondary battery 230: Sensor group

[Fig. 1] is an explanatory diagram of the structure of a battery performance evaluation device as one embodiment of the present invention. [Fig. 2] is a flowchart showing the procedure of the battery performance evaluation method of the target secondary battery. [Fig. 3A] is an explanatory diagram of the first battery model (complete model). [Fig. 3B] is an explanatory diagram of the second battery model (simplified model). [Fig. 4A] is an explanatory diagram of a Nyquist diagram of a complete model of a secondary battery. [Fig. 4B] is an explanatory diagram of a Nyquist diagram of a simplified model of a secondary battery. [Fig. 5A] is an explanatory diagram regarding the specified current. [Fig. 5B] is an explanatory diagram of the voltage response characteristics of the secondary battery and the battery model.

10:Database

100:Battery performance evaluation device

200:Target machine

Claims (5)

A battery performance evaluation device comprising: a first recognition processing element for recognizing a measurement result of the impedance of a reference secondary battery, based on the measurement result of the impedance of the reference secondary battery recognized by the first recognition processing element, when When the conditions are specified, the first battery model defined by the plurality of first model parameters is determined by verifying the respective values of the plurality of first model parameters. When the aforementioned specified conditions are satisfied, the first battery model is determined by verifying the respective values of the plurality of first model parameters. The first calculation processing element of the second battery model defined by the plurality of second model parameters is determined by the respective values of a smaller number of second model parameters, for the target secondary battery having the same specifications as the aforementioned reference secondary battery. The second recognition processing element for recognizing the actual measured output voltage that is a measurement result of the change pattern of the voltage output from the target secondary battery when a specified current is input, for the aforementioned first calculation processing element determined by the aforementioned first calculation processing element The battery model or the second battery model, a second calculation processing element that specifies the model output voltage as a change pattern of the voltage output by the first battery model or the second battery model when the specified current is input, and based on The battery performance evaluation element for evaluating the performance of the aforementioned target secondary battery is a comparison result between the aforementioned actual measured output voltage recognized by the aforementioned second recognition processing element and the aforementioned model output voltage specified by the aforementioned second calculation processing element, and the aforementioned first Calculation processing elements, convert the aforementioned specified current from a frequency ratio to a reference frequency The first battery model or the second battery model is established as the specified condition, at least one of the current component composition having a lower frequency and the calculation processing load of the first calculation processing element being greater than or equal to a reference value. For example, in the battery performance evaluation device of claim 1, each of the aforementioned first model parameter and the aforementioned second model parameter includes a parameter that defines the Whopper impedance, and the aforementioned second model parameter is a part of the parameter that defines the Whopper impedance, and the aforementioned parameter of the Whopper impedance is a part of the parameter. 1 is part of the model parameters and is common to the parameters that define the Warburg impedance. In the battery performance evaluation device of claim 1 or 2, the first recognition processing element recognizes the measurement results of the impedance of the reference secondary battery at various temperatures; the first calculation processing element is based on the above 1. Recognition processing elements recognize the aforementioned measurement results of the impedance of the secondary battery at various different temperatures by specifying the temperature dependence of the respective values of the aforementioned complex first model parameters when the aforementioned specified conditions are not met. When the aforementioned first battery model is satisfied, the aforementioned second battery model is determined by specifying the temperature dependence of respective values of the plurality of second model parameters; and the aforementioned second cognitive processing element is other than the aforementioned object. In addition to the aforementioned actual measured output voltage of the secondary battery, the measurement result of the temperature of the subject secondary battery is also known; the aforementioned second calculation processing element is used for the aforementioned first calculation processing element. When the first battery model or the second battery model whose elements are determined, in addition to the specified current, a measurement result of the temperature of the target secondary battery recognized by the second recognition processing element is input to the model. output voltage. A battery performance evaluation method, including: a first recognition process for recognizing a measurement result of the impedance of a reference secondary battery, based on the measurement result of the impedance of the reference secondary battery recognized in the first recognition process, when the specified In the case of conditions, the first battery model defined by the plurality of first model parameters is determined by verifying the respective values of the plurality of first model parameters. When the aforementioned specified conditions are met, the first battery model defined by the plurality of first model parameters is determined by verification. The first calculation process of determining the second battery model defined by the plurality of second model parameters for respective values of a small number of second model parameters is performed on a target secondary battery having the same specifications as the aforementioned reference secondary battery. A second recognition process for recognizing an actual measured output voltage that is a measurement result of a change pattern of a voltage output from the subject secondary battery when a specified current is input, for the first battery model determined by the first calculation process or The above-mentioned second battery model is a second calculation process for specifying a model output voltage as a change pattern of the voltage output by the first battery model or the second battery model when the above-mentioned designated current is input, and based on the above-mentioned 2. The difference between the aforementioned actual measured output voltage recognized by the recognition process and the aforementioned model output voltage specified by the aforementioned second calculation process. Comparing the results, the battery performance evaluation process for evaluating the performance of the aforementioned target secondary battery, the aforementioned first calculation processing process, the aforementioned specified current is composed of a current component with a lower frequency than the reference frequency, and the calculation of the aforementioned first calculation processing element At least one condition that the processing load is greater than or equal to the reference value is used as the specified condition to establish the first battery model or the second battery model. For example, in the battery performance evaluation method of claim 4, each of the aforementioned first model parameter and the aforementioned second model parameter includes a parameter that defines the Whopper impedance, and the aforementioned second model parameter is part of the parameter that defines the Whopper impedance, and the aforementioned second model parameter 1 is part of the model parameters and is common to the parameters that define the Warburg impedance.

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